Roystonea vs monocot genus

Roystonea and monocot genus both are nouns.

Word	Noun	Adjective	Verb	Adverb
Roystonea	Yes	No	No	No
monocot genus	Yes	No	No	No

As nouns, monocot genus is a hypernym of Roystonea; that is, monocot genus is a word with a broader meaning than Roystonea:

Roystonea: a monocotyledonous genus of West Indian feather palms
monocot genus: genus of flowering plants having a single cotyledon (embryonic leaf) in the seed

Other hypernyms of Roystonea include liliopsid genus.

Roystonea (noun)	monocot genus (noun)
a monocotyledonous genus of West Indian feather palms	genus of flowering plants having a single cotyledon (embryonic leaf) in the seed